class MaintenanceEntriesController < ApplicationController
  ODOMETER_WARNING_THRESHOLD = 500

  def create
    @vehicle = Vehicle.find(params[:vehicle_id])
    original_odometer = @vehicle.current_odometer
    @maintenance_entry = @vehicle.maintenance_entries.build(maintenance_entry_params)
    @maintenance_entry.updated_by_user = Current.user

    if save_maintenance_entry
      set_old_odometer_warning(original_odometer)
      redirect_to @vehicle, notice: "Maintenance entry recorded."
    else
      prepare_vehicle_show
      render "vehicles/show", status: :unprocessable_entity
    end
  end

  private

  def maintenance_entry_params
    params.require(:maintenance_entry).permit(:name, :notes, :odometer, :cost, :date)
  end

  def save_maintenance_entry
    saved = false

    MaintenanceEntry.transaction do
      if @maintenance_entry.save
        update_vehicle_odometer(@maintenance_entry.odometer)
        saved = true
      end
    end

    saved
  end

  def update_vehicle_odometer(odometer)
    return unless odometer > @vehicle.current_odometer

    @vehicle.update!(current_odometer: odometer)
  end

  def set_old_odometer_warning(original_odometer)
    return unless @maintenance_entry.odometer < original_odometer - ODOMETER_WARNING_THRESHOLD

    message = "Maintenance odometer is more than 500 miles behind the current vehicle odometer."
    flash[:warning] = message
    Rails.logger.warn(
      "#{message} vehicle_id=#{@vehicle.id} maintenance_entry_id=#{@maintenance_entry.id} " \
        "entry_odometer=#{@maintenance_entry.odometer} vehicle_odometer=#{original_odometer}"
    )
  end

  def prepare_vehicle_show
    @maintenance_schedules = @vehicle.maintenance_schedules.order(:maintenance_type)
    @fuel_entries = @vehicle.fuel_entries.includes(:updated_by_user).order(date: :desc, created_at: :desc)
    @maintenance_entries = @vehicle.maintenance_entries.includes(:updated_by_user).order(date: :desc, created_at: :desc)
    @fuel_entry = @vehicle.fuel_entries.build(date: Date.current)
  end
end